Quote:
Originally Posted by Yamamaya42
1) remove osc tube, did that...
2) DC probe at junction of R40-R41, adjust “contrast” to -3 volts, leave it there.
This did not work, it cut off all input from tuner/if , no input defection at all, had to take it up to -1.2 to get it to do anything, and when I did try at that point, it ended up worse than when I started.
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Sure seems to indicate a lack of gain in the tuner, which coincides with snow in picture. I wonder what would happen if you inject your alignment signal to a tube shield hovering over the local oscillator tube, so it's not grounded. That should capacity couple the signal so it's fed to the first IF stage. If that doesn't work I'd try through a capacitor to the first IF grid. [edit] forgot to mention you need to snip I think pin 1 on a 6J6 to capacity couple through a shield over a 6j6, which I think is the plate. Basically disables the oscillator and couples to the 2nd rf tube.